1. Field of the Invention
The present invention relates to a vehicle air conditioner with a discharge capacity control of a compressor. The vehicle air conditioner performs a cool storage in a cooling heat exchanger during a vehicle deceleration to recover deceleration energy of the vehicle.
2. Description of Related Art
In a conventional vehicle air conditioner, a temperature of air cooled by an evaporator is detected by a temperature sensor, and a driving control of a compressor is performed so that a detected temperature of the temperature sensor becomes a target cooling temperature (e.g., JP-A-57-44511, JP-A-2001-105846). Furthermore, during a vehicle deceleration, the target cooling temperature is decreased more than that before the vehicle deceleration and, an operation ratio (working ratio) of the compressor is increased, so that deceleration energy of the vehicle is recovered.
In this vehicle air conditioner, when a variable displacement compressor is used, the displacement (discharge capacity) of the compressor is gradually increased in accordance with the detected temperature when the target cooling temperature is reduced. Accordingly, when the vehicle deceleration is finished, the discharge capacity of the compressor may be not increased to the maximum capacity, and the deceleration energy cannot be recovered sufficiently.